1. Field of the Invention
The present invention relates to drain sumps and, more particularly, to a safety device for a drain sump that is structured to prevent an individual or object from obstructing the flow of water entering the opening of a drain pipe in communication with a pool pump.
2. Discussion of the Related Art
Generally, one or two main drains are included on a swimming pool's floor or side wall as part of the swimming pool circulation system, which drains and filters pool water prior to directing the water back into the swimming pool. A drain sump at the swimming pool floor is in communication with the main drain and includes a drain grate for blocking access to the drain sump. The primary force in draining the pool water is the suction produced by the pool pump, which pulls water from the swimming pool into the main drain(s). The considerably high amount of suction produced by the pool pump has resulted in a number of accidents involving individuals swimming in the vicinity of the drain sump being trapped against the drain grate, creating a vacuum within the main drain between the obstruction and the pool pump, which can result in serious injury and/or death by drowning. In cases where the drain grate is damaged or missing, the visible opening creates an attractive nuisance to children who are likely to inspect the exposed drain sump and possibly get their arm or leg caught in the drain pipe, making it extremely difficult to pry the child to safety. There are five common types of entrapment include (1) limb entrapment, wherein a portion of an individual's limb gets pulled into the sump or skimmer orifice; (2) mechanical entrapment, wherein a user's entrapped limb undergoes edema or swelling due to the intense vacuum force; (3) hair entrapment, wherein an individual's hair gets tangled around the drain cover (4) body entrapment, wherein an individual covers the entire opening of the drain or skimmer and the vacuum force from the pump creates the entrapment; and (5) evisceration, wherein an individual, usually a child, sits on the drain creating a blockage where the intense vacuum force pulls the intestines out of the body and through the piping system.
In order to combat this issue, a number of attempts have been directed towards improving the design of the main drain and drain sump. One example of such an attempt is provided in U.S. Pat. No. 7,455,070 to Hamza, which discloses a vacuum relief safety valve attached to a pool pump and having an air inlet aperture exposed to ambient air and a sealing element which is pressed against the aperture by a spring. In the event that the maximum allowed vacuum level in the pump is exceeded, the sealing element moves into the inner chamber and opens the air inlet aperture, causing the pump to lose its prime. The '070 patent, while useful for its intended purpose, does not provide adequate assurance of an entrapped swimmer's escape due to the requirement that the obstructing object or swimmer must actually create a vacuum force in to trigger the maximum vacuum level and open the air inlet valve. The '070 patent and others fail to provide a simple and effective design for preventing entrapment of a swimmer within a drain sump.
Therefore, there remains a need for a safety device for drain sumps that prevents an individual from being entrapped by the suction force produced by a pool pump in the event that a person obstructs the flow of water through the main drain pipe in connection with the pool pump, thereby allowing the person to safely escape entrapment.